Well, we’ve reached the last planet – Neptune! But we’re not done yet because we have a 10th unit which will deal with other bodies in the Solar System. This unit, Planet: Neptune, concentrates on the qualitative facts we’ve learned so far such as distances, calculating distances, eccentricities, and axial tilts. In addition, student learn a new concept – how to calculate travel times for very long distances when they try to determine how long it will take to travel to the nearest star system, Proxima Centauri.

To illustrate how impractical space travel is (at this point in time) for humans I am suggesting the students try their hand at reading some early classic science fiction about the concept of a “generation ship”. The book is called Orphans of the Sky and was written by Robert A. Heinlein. It was originally a radio program in the 1940’s and can be found on Amazon in mass market paperback, as Kindle download, and on Audible as an audiobook. (Audible has a free books trial – so if you use the free trial you could get it for free). It is a short book at less than 200 pages and don’t let the cheesy cover fool you – this is a solid read that is suitable for ages 10 and up (in my opinion).

The unit also contains all the usual facts about the planet including rings, moons, and composition and there is an additional supplemental worksheet for calculating their weight on other planets that can be downloaded here.